The present invention concerns a wearing part system comprising a wearing part holder and a wearing part, where the wearing part and the wearing part holder together define a locking opening. Moreover, the invention deals with a lock and a method of releasable locking of a wearing part to a wearing part holder in a wearing part system with lock.
Various forms of construction machinery, such as excavating machines, wheel loaders, backhoe loaders, or other types of machines suitable for digging or otherwise working or moving material or sediment typically use digging teeth or other replaceable wearing parts or tools mounted on the bucket or the implement used to work or move the material. For construction machinery designed to work the material or sediment with digging teeth in most cases there occurs a wearing of the digging teeth with which the construction machine is outfitted. The digging teeth are designed to be replaced after wearing down and the digging teeth are configured to work or clear the material being handled by the construction machine in various ways. A wearing part such as a digging tooth is mounted on the bucket, for example, by a screw connection or wedge connection, various forms of thermal mounting, such as welding or a shrink connection are other known mounting methods.
The digging tooth can be mounted on a wearing part holder or tool holder and replaced in ongoing manner. Forces acting on the tool affect the wearing part holder and after a lengthy period of use the wearing part holder may also need to be replaced.
Traditionally, the wearing part holder is welded, or mounted by some other thermal joining technique, on the bucket or implement. But it is also conceivable to mount the wearing part holder with a screw connection, wedge connection, or other mechanical mounting method. It also happens that the digging tooth is mounted directly on the bucket or implement.
Patent document U.S. Pat. No. 5,956,874 describes a locking system for locking a digging tooth to an adapter. The patent document describes an essentially hollow digging tooth configured with a first opening and second opening, where the openings are configured in walls of the digging tooth where the digging tooth is designed to enclose an adapter with a cavity running through the adapter. When the digging tooth is arranged on the adapter, a mounting hole is defined by the first opening of the digging tooth, the cavity of the adapter, and the second opening of the digging tooth, through which a locking pin can be installed. The locking pin is mounted through the first opening, through the adapter, and in the second opening of the digging tooth. When the locking pin is mounted, the locking pin can be retained with a lock washer which is introduced into the first opening when the locking pin is installed. The lock washer is designed with an inner metal ring and an outer rubber ring, where the inner metal ring is designed with a hole. The lock washer is mounted and dismounted with a tool. U.S. Pat. No. 5,956,874 states that a screwdriver can be used. One problem with the existing technical solution is that the lock washer wears down, shifts, or is otherwise removed, so that when the locking system is used the locking pin drops out and loosens the digging tooth from the adapter.
Known mounting methods which effectively lock the digging tooth have proven to be difficult to handle, while mounting methods which facilitate replacement of the digging teeth are deficient in regard to locking of the digging tooth on the wearing part holder. It is desirable to solve the above problems by the development of an easily releasable lock for fixing a digging tooth/wearing part to a wearing part holder in a secure, simple and durable manner.
One purpose of an aspect of the present invention is to provide the technical area with a lock for a wearing part system for easy and improved holding, secured and/or fixed mounting or arrangement of a wearing part on a holder.
The second purpose of an aspect of the invention is described in further detail in connection with the detailed description of the invention.
The invention, according to an aspect thereof, concerns a wearing part system comprising a wearing part holder, a wearing part, where the wearing part and the wearing part holder jointly define at least one locking opening; at least one wedge for locking of the wearing part to the wearing part holder, where the wearing part is arranged with at least one rotatable rotary disk, where the rotary disk can be arranged in a first open position and a second closed position, and the wedge can move in the locking opening through the rotary disk, when the rotary disk is oriented in a first open position, and the wedge is locked and retains the wearing part against the wearing part holder when the rotary disk is oriented in a second closed position.
According to further aspects of the improved wearing part system for releasable locking of a wearing part to a wearing part holder in a wearing part system:
the wearing part is a digging tooth;
the rotary disk is designed with two mounting holes, a space, and at least one flexible notch, which together make it possible to compress the rotary disk when installing the rotary disk in a groove made in the wearing part;
the rotary disk is designed with at least one socket for retaining of the rotary disk in the closed position when the socket encounters an elevation produced in the wearing part;
the rotary disk is arranged with a rectangular tool notch adapted to a rotary tool;
the wearing part holder, in the locking opening, is designed with a cavity passing through the wearing part holder to receive the wedge when it is placed in the locking opening;
the wearing part in the locking opening is arranged with a groove produced in the first opening of the wearing part, in which groove the rotary disk is arranged;
the wearing part, at the second opening arranged on the wearing part, is arranged with a socket and a shoulder against which the wedge bears;
the area formed by the first cross section of the wedge and the second cross section of the wedge is oval and the wedge is conical in the longitudinal dimension of the wedge with an angle in the range of 0.1 degrees to 5 degrees.
Moreover, an aspect of the invention consists of or comprises a lock for releasable locking of a wearing part to a wearing part holder in a wearing part system where the wearing part and the wearing part holder together define a locking opening to receive the lock, where the lock comprises a wedge, where the lock further comprises a rotatably disposed rotary disk, where the rotary disk can be oriented in a first open state, the first open position, and a second closed state, the second closed position, where the rotary disk is arranged in a groove produced in the wearing part at the first opening, where the first opening is arranged in the wearing part.
Moreover, the invention concerns a method for releasable locking of a wearing part to a wearing part holder in a wearing part system comprising a wedge, wherein the wearing part is arranged with a rotatable rotary disk, which involves the following steps:
i) the wearing part is arranged on the wearing part holder;
ii) the rotary disk is oriented in a first open position;
iii) the wedge is arranged in a locking opening defined by the wearing part and the wearing part holder;
iv) the rotary disk is oriented to a second closed position so that the wedge is held in the mounted state.